ON THE ASSIMILATION OF GNSS PWV MEASUREMENTS IN HEAVY TO TORRENTIAL RAIN EVENTS IN DAVAO CITY, PHILIPPINES

A standalone Global Navigation Satellite System (GNSS) receiver was utilized in this study to get a measure of the atmospheric water vapor in Davao City, Philippines. It aims to monitor the variability of GNSS precipitable water vapor (PWV) especially during heavy to torrential rain. The results of the study showed a positive correlation between GNSS-PWV and precipitation especially in these severe (heavy to torrential) rain events which implies that the assimilation of atmospheric water vapor measurements can improve forecasts of such events

On the variability of precipitable water vapor and its probabilistic modeling of precipitation occurrence in Davao City

This study utilized the data files from the local radiosonde station in Davao City to monitor the atmospheric water vapor content in the area. Results of the study showed that the PWV derived from the local radiosonde station was able to provide annual, seasonal and monthly variations of the atmospheric water vapor content in Davao City. A probabilistic modeling of precipitation occurrence utilizing the PWV values was also explored in this study. REEP and logical regression analyses were performed on the three-year (2013-2015) PWV and rainfall data to determine the critical PWV value that would predict a positive or negative probability of rain occurrence. The calculation of odd ratio also showed that the odds of raining increase exponentially as PWV accumulate. © 2017 American Scientific Publishers. All rights reserved